Eps foam melt

General Discussion
1

Ok… So I went to rout a new fcs handle into my sup.( As I have done in the past many times) The handle in there was a cheap one that was centered to the board and not balanced for the fin, which made it impossible to carry. The blank is 1.5 lb foam. 

I routed the old handle out and filled it with some old foam and poured a slurry of white tinted epoxy with micro balloons… Kind of thick, but still pourable. Next thing you know… The resin seems to be draining and starting to smoke!!! Wtf… Big melt out spot right through to the bottom … Ouch!!!  I’ve probably set over 100 fusion boxes on my own boards and never had the heat build up this produced. Ive never even had any foam melt at all… Any ideas on how to go about filling in this nightmare without any further melting. Slow hardener??? Fix deck… Sand and hotcoat…then cut out bottom glass and fill the rest… ?  I guess. 

2

I had similar but not as serious problems on a 1.5 US Blanks eps blank when I put boxes in with Resin Research Fast hardener.  I noticed bubbling but, being a noob, thought it was air bubbles.  It was melting.  2nd surf, the drive side box blew out.

I:

  1. put a 1/8" (thick) mesonite square over the box (after removing screws, etc.),

  2. used a router to rout out the foam and mesonite at the same time, making sure the router bit would cut deeper than the bit for the box itself (when putting the box in, later),

  3. used the routed mesonite hole to draw the hole’s shape onto a block of poly a bit thicker than the hole I’d routed

  4. cut the poly to shape with a saw, sanded one side of it flat, and sanded the outline to match the hole

  5. epoxied the poly plug into the hole using SLOW Resin Research hardener

  6. sanded the plug down to allow for lam and hotcoat

  7. painted, lammed, and hotcoated the plug to be flush with the original board

  8. installed my replacement box.

It came out sturdy and great.

Then I went for a two surfs and immediately blew out the center fin, just surfing normally.

3

Pictures?

4

I’ve never seen anything like it!!!

2448×3264 1.93 MB

5

In between the good foam and bad stuff is the bottom lamination of a 5 inch thick board, With a foam stain panel … Could almost make out the colors 

6

Solution?  Polyurethane foam. Or, glass them on. Mike

7

Thanks rooster… I was gonna fill it with some poly foam… Then do a nice clean topside repair over the handle. It will be covered with a pad so I’m not worried. And then fill and repair again from the bottom up… 

8

have to ask if you are sure you got the ratio right on the epoxy.  looks like an accident I had when FedEx interupted me while pouring and I went 1 to 1 on the harder and resin.  melted out of the bottom with a lot of fumes and drama.  hilarious.  if I hadn’t spent so much time shaping it.

9

Oh man that sucks!!! The joys of epoxy!  I am 100% positive the mix was right. I know the blank was 1.5 lb eps ( at best… Cause I shaped it). 2lb is so much nicer foam.  This thing was smoking so bad , and and smelled terribly!!!  Never had that happen… It was also the first time with lighter density stuff. I have no idea. I’ll get it nice… Just sucks the boards out of commission for a bit.